1. Field of the Invention
This invention relates generally to land vehicles and more particularly to those of the wheeled type having tandem drive axles.
2. Description of the Prior Art
Presently, anti-roll devices are provided on vehicles with single drive axles and those devices have been combined with resilient suspension members to provide vertical cushioning. Anti-roll devices are also provided on tandem axles to provide some anti-roll stiffness but do not provide soft vertical cushioning for good ride characteristics or maintain equal tire loading. Insufficient anti-roll stiffness causes heavy duty vehicle tandem axles to have poor dynamic characteristics in turns. Such vehicles are generally of the class 8 type having high gross weight/high center of gravity characteristics and are primarily used for heavy hauling. Examples of such vehicles include ready mix, sanitation collection, coal haulers, construction, and the like.
In view of the above, it would be advantageous to provide a suspension system for heavy duty tandem axle vehicles having sufficient stiffness and anti-roll characteristics and also having vertical softness or cushioning for good ride characteristics without sacrificing axle load sharing, which overcomes the problems associated with the prior art.